The Queen heads to church while Philip remains in hospital

It's business as usual for the Queen as she attends church in Sandringham while Prince Philip remains in a London hospital.

Her Majesty attended Sunday mass as usual, daughter-in-law Sophie, Countess of Wessex by her side as the pair gear up for royal Christmas at Sandringham.

If the monarch is concerned for her husband's health, she showed no signs of it, looking quietly composed as she rode to and from St. Mary Magdalene Church.

Queen Elizabeth II leaves after attending a church service at St Mary Magdalene Church in Sandringham. (PA/AAP)

Prince Philip, 98, was admitted to hospital on Friday for "observation and treatment in relation to a pre-existing condition," the statement from the Palace read, confirming the visit wasn't an emergency.

But the prince's long history of health concerns has royal fans – and perhaps the royal family themselves – fearing that he may not make it back to Sandringham for Christmas.

Palace officials reported on Friday that Philip would remain at King Edward VII Hospital for a few days but did not say whether he would be discharged in time for the holidays.

Prince Philip, the Duke of Edinburgh, was admitted to hospital on Friday. (AAP)

But the prince is reportedly hopeful, joking with doctors that he hopes to be well enough to return to Sandringham for the festivities.

The Queen's appearance today has also reassured the public, well-wishers who spotted her outside the church saying that her calm demeanour was a good sign.

Usually all of the senior royals attend the family get-together, but there will be a few key players missing this year: the Sussexes.

Prince Harry and Meghan Markle announced last month that they would not be spending the holidays with the rest of the family, and it was recently confirmed that the couple have travelled to Canada with young son Archie for Christmas.